New Belgian guidelines for pattern imprinted concrete pavements

Abstract

Pattern imprinted concrete is a decorative type of concrete pavement that is mainly used in public spaces but also on traffic islands, truck aprons of roundabouts and sometimes on roads, dedicated bus lanes or tramways. The Belgian standard tender specifications for road construction provide two options: a first one using a colour-hardener on the surface and a second one with full depth coloured concrete. In addition, printing can be done with plastic moulds that can be manipulated by hand, or a roller can be used by which means the print pattern is applied. And finally, the concrete can be put in place between fixed formworks, or, in exceptional cases, with a slipform paver.

The Belgian Road Research Centre created a new working group in 2022 to improve and update the guidelines for the design and construction of pattern imprinted concrete pavements (PICP). Based on the options mentioned above, different categories of construction solutions are created. For each of the categories, the specifications have been discussed regarding:

• description of the specific materials: colour-hardener, release agent, surface sealer, etc.
• the concrete mix and its constituents;
• requirements on fresh and hardened concrete;
• construction: compaction – curing – cleaning – surface protection;
• surface characteristics (skid or slip resistance, evenness);
• visual inspection and evaluation.

The new guidelines and updated specifications should lead to a better understanding of the different solutions and best practices by both road authorities and contractors, and are aimed to enhance the quality of PICP in Belgium.